// -*- mode:c++; tab-width:2; indent-tabs-mode:nil; c-basic-offset:2 -*-
/*
 *  GreyscaleLuminanceSource.cpp
 *  zxing
 *
 *  Copyright 2010 ZXing authors All rights reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <zxing/common/GreyscaleLuminanceSource.h>
#include <zxing/common/GreyscaleRotatedLuminanceSource.h>
#include <zxing/common/IllegalArgumentException.h>

using zxing::Ref;
using zxing::ArrayRef;
using zxing::LuminanceSource;
using zxing::GreyscaleLuminanceSource;

GreyscaleLuminanceSource::
GreyscaleLuminanceSource(ArrayRef<char> greyData,
                         int dataWidth, int dataHeight,
                         int left, int top,
                         int width, int height)
        : Super(width, height),
          greyData_(greyData),
          dataWidth_(dataWidth), dataHeight_(dataHeight),
          left_(left), top_(top) {

    if (left + width > dataWidth || top + height > dataHeight || top < 0 || left < 0) {
        throw IllegalArgumentException("Crop rectangle does not fit within image data.");
    }
}

ArrayRef<char> GreyscaleLuminanceSource::getRow(int y, ArrayRef<char> row) const {
    if (y < 0 || y >= this->getHeight()) {
        throw IllegalArgumentException("Requested row is outside the image.");
    }
    int width = getWidth();
    if (!row || row->size() < width) {
        ArrayRef<char> temp(width);
        row = temp;
    }
    int offset = (y + top_) * dataWidth_ + left_;
    memcpy(&row[0], &greyData_[offset], width);
    return row;
}

ArrayRef<char> GreyscaleLuminanceSource::getMatrix() const {
    int size = getWidth() * getHeight();
    ArrayRef<char> result(size);
    if (left_ == 0 && top_ == 0 && dataWidth_ == getWidth() && dataHeight_ == getHeight()) {
        memcpy(&result[0], &greyData_[0], size);
    } else {
        for (int row = 0; row < getHeight(); row++) {
            memcpy(&result[row * getWidth()], &greyData_[(top_ + row) * dataWidth_ + left_],
                   getWidth());
        }
    }
    return result;
}

Ref<LuminanceSource> GreyscaleLuminanceSource::rotateCounterClockwise() const {
    // Intentionally flip the left, top, width, and height arguments as
    // needed. dataWidth and dataHeight are always kept unrotated.
    Ref<LuminanceSource> result(
            new GreyscaleRotatedLuminanceSource(greyData_,
                                                dataWidth_, dataHeight_,
                                                top_, left_, getHeight(), getWidth()));
    return result;
}
